Hydraulic jack



Aug, BE, 1923;.

J. A. ROSS HYDRAULIC JACK 2 Sheets-Sheefi :1

Filed Oct.

Aug. 21, 1923.

J. A. ROSS HYDRAULIC JACK Filed Oct. 2. 1922 2 Sheets-Sheet 2 Patented Aug. 21, 1923.

UNITED STATES I" 9 59365 PAT JAMES ALFRED R088, 01 UPPER HOLLOWAY, LONDON, ENGLAND.

HYDRAULIC JACK.

Application filed October 2,1922. Serial No. 591,962.

road vehicles in which the base forms the reservoir for the liquid, and it has for its object to simplify the construction and thereby reduce the cost of manufacture. Another object of this invention is to make the jack more reliable in action and less liable to derangement by wear and tear.

I attain these ends. by the construction shown in the accompanying drawings in which :Figure 1 is a view in sectional elevation of a jack having a telescopic ram;

Fig. 2 is a view in plan on the underside of the jack, and Fig. 3 is a view in sectional elevation on line w a: Fig. 2.

Throughout the views similar arts are marked with like numerals of re erence.

The cylinder 1 which carries the telesco ic ram is formed in one' piece with a shell 2 which is preferably of rectangular form and which with the bottom plate 3 forms the reservoir, said plate, which forms the base of the jack, being secured to the'bottom of said shell by a plurality of screws '4. The barrel 5 of the force pump which is provided with the usual plunger 6 is formed by a bush 7 located at one end of the shell 2 and provided at its lower end with a port 8 which opens into the reservoir and is adapted to be closed by a ball valve 9. 'From the lower end of the barrel 5 of the force pump is a passage 10 formed in a rib 11 on the wall of the shell. 2 running between said barrel 5 and the lower end of the ram cylinder 1 said passage putting the barrel 5 into communication with the said cylinder 1. The lower end of the ram cylinder l-is closed by a screw plug 12 which is provided with an annular recess 13 which when the plu is screwed home isin communication wit said passage 10. In the plug 12 is a non-return ball valve 14.- which places the annular recess 13 through a small passage 14 in communication withsaid ball valve. By this construction the necessity of providing that the passages 10 and 14 are brought into register when the plug is screwed home in the cylinder 1 is avoided.

The non-return valve 15 in the main ram 16 is preferably of the ball type as shown in Fig. 1 and in order to lift it off its seating when the main'piston 16 descendsin order to release the liquid within it to permit the secondary ram 17 to descend-a pin 18 is mounted on the plug 12 to lift the ball valve 15 from its seating.

For the pu ose of releasing the fluid from the cylin er 1 to allow the ram 16 to descend a passage 19 is provided in a rib 20 on the wall of the shell 2 which runs be tween said cylinder and one end of said shell said passage 19 being in communication with the cylinder 1 by means of a passage 21 in a rib 22 on the wall of the shell running between said cylinder and said shell.

The other end of the passage 19 is closed by a valve 23 which is'provided with a bypass 24 leading back into the reservoir.

The passage between the upper end of the cylinder 1 and the reservoir for relieving the hydraulic pressure when the ram 16 has reached the limit of its upward travel may be formed in the wall of said cylinder or in a rib on the exterior thereof but is preferably formed by a pipe 25 which is connected to a port in the wall of said cylinder and passes into the reservoir through the top of the shell 2 by an air tight connection, after which it is preferably bent to bring its free end into register with the filling orifice of the reservoir for the purpose of avoiding any syphon action in said pipe said orifice being closed by a plug 26 in the usual manner.

The other parts of the jack are of the usual construction as shown in the accompanying drawings and call for no further description.

What I claim is 1. In a hydraulic jack the combination with the ram and its working cylinder, of a shell formed integral with said cylinder, a detachable plate adapted to form the base of the shell and to co-act with it to form a reservoir for the liquid, passages in the walls of said-shell for the circulation of the liquid, a screw plug closing the lower end of the ram cylinder within the shell base and a non-return valve located in said plug.

2. In a hydraulic jack the combination with the ram and its working cylinder, of a shell formed integral with said cylinder, a detachable plate adapted to form the base v having afillin walls of'said shell for the circulation of the liquid, a screw plug closing the lower end of the ram cylinder within the shell base, a non-return valve located in said plug and an annular recess in said screw plug which registers with the fluid delivery passage and has a port leading to said non-return valve.

3. In a hydraulic jack the combination with the ram and its working cylinder, of a shell formed integral with said cylinder, a detachable plate adapted to form the base of the shell and co-act with it to form a reservoir for the liquid, passages formed in ribs on the innerwalls of said shell for the circulation of the liquid, a screw plug closing the lower end of the ram cylinder with in the shell base, anon-return valve located in said plug, and a release valve in direct communlcation'. with the lower end of the cvlinder'of the ram.

4. In a hydraulic jack the combination -with the ram and its working cylinder, of

a shell formed integral with said cylinder, a detachable plate adapted to form the base of the shell and'co-act with it to form a reservoir for the liquid, passages formed in ribs on the inner walls'of said shell for the circulation of the liquid, a screw plug closing the lower end of the ram cylinder within the shell base, a non-return valve located in said lug, an annular recess in saidscrew plug which register with the fluid delivery-passage and has a port leading to the non-return valve, and a release valve in direct communication with the lower end of the c linder of the ram.

5. n a hydraulic jack the combination with a ram and its working cylinder, of a shell formed integral with said cylinder and orifice closed by a screw plug, a detachable p ate adapted to form the base of the shell and co-act with it to form a reservoir for the liquid, passages in the wall of the shell for the circulation of the li uid, and a passage between the upper end 0 the ram cylinder and the reservoir the lower end of which is curved to bring its orifice into alignment with the filling orifice.

annular recess in said 6. In a hydraulic jack the combination with a ram and its working cylinder, of l. shell formed integral with said c linder and having a filling orifice closed y a screw plug, a detachable plate adapted to form the base of the shell and co-act with it to form a reservoir for the liquid, passa es in the wall of the shell for the circulation of the liquid, a passage between the upper end of the ram cylinder and the reservoir the lower end of which is curved to bring its orifice into alignment with the filling orifice, a screw plug closing the lower end of the ram cylinder within the reservoir and'a non-return valve in said lug. J

7. In a hydraulic jack the combination with a ram and its working cylinder of a shell formed inte al with, said 0 linder and having a, fillifig orifice closed b a screw plu a detachable plate adapted to form the'%ase of the shell and co-act with it to form a reservoir for the liquid, passages in the wall of the shell for the lation of the liquid, a passage between'the upper end of the ram cylinder and the reservoir the lower end of which is curved to bring its orific into alignment with the filling orifice, end of the ram cylinder within the reser- V011, a' non-return valve in said plu and an screw plugfw ich registers with the fluid delivery passage and has a port leadin to the non-return valve.

8. In a hydrau ic 'ack the combination of a ram and its wor ing cylinder, a shell formed integral with said cylinder and havmg a fillin orifice closed by a screw lug, a etachab e plate forming the base oi the shell and coacting with said shell to form a reservoir for the liquid, passages in the wall of the shell for the circulation of the liquld, a passage between the upper end of the ram c linder and the reservoir the lower end of which is curved to bring its orifice into alignment with the filling orifice, and a release valve in direct communication with the lower end of the cylinder of the ram.

JAMES ALFRED ROSS.

circa-v a screw plug closing the lower. 

